The deadly love triangle plot played out in Herndon, Virginia
Juliana Peres Magalhães, the nanny for a suburban Virginia family who pleaded guilty to manslaughter last month in a double homicide case, can be seen hyperventilating in new police body camera footage from the Fairfax County Police Department.
Magalhães, a Brazilian national, apparently fell in love with her employer, former IRS agent Brendan Banfield, and the pair have been accused of staging a complex plot to murder Banfield's wife, Christine Banfield, the mother of his 4-year-old daughter, in February 2023.
An man named Joe Ryan was also killed as part of the alleged scheme after prosecutors say he was contacted on a sexual fetish website and lured to the Banfields' home with the promise of sex.
In the February 2023 video, Magalhães can be heard telling police her "husband" is downstairs.
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Juliana Peres Magalhães in new police bodycam footage calling Brendan Banfield her "husband." (Fairfax County Police Department via AP)
"He started stabbing her," Magalhães told police in the video, referring to Ryan. "I think Brendan shot him, and he asked me [for] help shooting him. … I never saw him before."
She was 22 when police initially arrested her in October 2023, about eight months after the killings, when authorities charged her with aggravated murder and use of a gun in commission of a felony.
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Brendan Banfield is charged with four counts of aggravated murder and use of a gun in commission of a felony. (Fairfax County Police Department)
At the time of her arrest, she had moved into the main bedroom of the Banfields' Herndon home, with a photo of herself and Brendan together on a nightstand beside the bed, according to authorities.
Fairfax County Police arrested Banfield, a 39-year-old IRS employee, in September, more than a year after the murders. He is charged with four counts of aggravated murder and use of a gun in the commission of a felony.
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This image provided by the Fairfax County Police Department and taken Oct. 13, 2023, was submitted as evidence in the murder case against Brendan Banfield. It shows a framed photo of Banfield and Juliana Peres Magalhães on his bedside table in Herndon, Va. (Fairfax County Police Department via AP)
Banfield faces a potential life prison sentence for the alleged crimes, while Magalhães faces a maximum sentence of 10 years for the manslaughter charge, according to FOX 5.
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When police responded to a 911 call from the Banfield residence Feb. 24, 2023, they found Christine with stab wounds to the neck and Ryan with fatal gunshot wounds in the upstairs bedroom of the home. Authorities took Christine to the hospital, where she was later pronounced dead.
Christine Banfield was stabbed to death in the bedroom of her Fairfax County, Virginia, home. (Facebook)
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Officials recovered a knife and two guns from the house.
It remains unclear exactly what transpired inside the home that Friday morning, but Magalhães and Brendan apparently both admitted to shooting Ryan while the man was holding a knife to Christine.
Magalhães is charged with second-degree murder and use of a deadly weapon during the commission of a crime. (Instagram)
Viviane Magalhães, Juliana's stepmother, told The Associated Press she hopes her stepdaughter can return home to Brazil soon.
"We still can't figure this out. I believe she was fooled by this guy. He brainwashed her," Viviane Magalhães told the AP in Portuguese, referring to Banfield. "She was never a gold digger in Brazil. For many years, she dated a man who was as humble as she was. We could never think of her living a situation like this."
Banfield is no longer employed by the IRS.
The Associated Press contributed to this report.
Audrey Conklin is a digital reporter for Fox News Digital and FOX Business. Email tips to